The present disclosure generally relates to fasteners, and more particularly, to active material based fasteners, such as cable ties and twist ties, that can be reversible.
Fasteners such as hose clamps and cable ties are commonly employed at different stages of the manufacturing process to secure objects together such as a hose and a connector or a bundle of wire. In the case of a hose clamp, it can be difficult to ascertain visually whether the clamp has been tightened to a degree effective to prevent leakage. Even if adequately tightened during the initial assembly process in an amount effective to prevent leakage, it is possible that a hose clamp can loosen due to the vibrations of the operating environment. Still further, for automotive applications, metal-based hose clamps are used to connect radiator hoses to a radiator inlet that is subject to extensive thermal cycling. This exposure of the metal-based hose clamp to thermal cycling could adversely affect the properties of the metal, compromising the ability of the clamp to prevent leakage.
FIG. 1 illustrates an exemplary prior hose clamp 10 for use in securing a hose. Such hose clamps can be formed of an elongated member of stainless steel. As shown, a band 12 having first and second opposed ends which are overlapped to form an annular member includes outer stamped threads (or perforations) 14 and an adjustment assembly 16 in operative communication therewith to define a worm drive for selectively adjusting the diameter of the annular member. The adjustment assembly 16 includes drive gear having peripheral teeth that engage the stamped threads 14 whereby rotation of the gear results in the first and second ends moving to vary the circumference of the annular member. The drive gear is driven with an adjustment screw 17 that is positioned perpendicular to the annular member circumference for easier access. By adjusting the diameter of the annular member, a hose 18 can be removed or secured to a hose connector 20.
Current fasteners like the one shown in FIG. 1, including cable ties, can require the use of some physical action and/or mechanical action to engage or release an object. For example, the hose clamp 10 in FIG. 1 can be tightened or loosened around a hose by physically turning the adjustment screw 17. The use of mechanical parts to control the tightness of a fastener can be problematic since the operation of mechanical parts is likely to fail. Moreover, physically adjusting the tightness of multiple fasteners can become a tedious process. Additionally, access to the mechanical means of adjustment may be limited.